Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        "Rafael J. Wysocki" <rafael@kernel.org>,
        linux-kernel@vger.kernel.org
Cc:     Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Subject: [PATCH v1 2/3] driver core: Read atomic counter once in driver_probe_done()
Date:   Mon,  9 Mar 2020 16:11:10 +0200
Message-Id: <20200309141111.40576-2-andriy.shevchenko@linux.intel.com>
In-Reply-To: <20200309141111.40576-1-andriy.shevchenko@linux.intel.com>
References: <20200309141111.40576-1-andriy.shevchenko@linux.intel.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

Between printing the debug message and actual check atomic counter can be
altered. For better debugging experience read atomic counter value only once.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/base/dd.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/base/dd.c b/drivers/base/dd.c
index 43720beb5300..efd0e4c16ba5 100644
--- a/drivers/base/dd.c
+++ b/drivers/base/dd.c
@@ -669,9 +669,10 @@ static int really_probe_debug(struct device *dev, struct device_driver *drv)
  */
 int driver_probe_done(void)
 {
-	pr_debug("%s: probe_count = %d\n", __func__,
-		 atomic_read(&probe_count));
-	if (atomic_read(&probe_count))
+	int local_probe_count = atomic_read(&probe_count);
+
+	pr_debug("%s: probe_count = %d\n", __func__, local_probe_count);
+	if (local_probe_count)
 		return -EBUSY;
 	return 0;
 }
-- 
2.25.1